<p>Nature-based Solutions (NbS) are increasingly promoted as sustainable and multifunctional climate adaptation measures; however, empirical evidence of their effectiveness in high-risk-prone nations like Ethiopia remains limited. This systematic review synthesized evidence from 26 peer-reviewed and grey literature sources documenting 35 NbS interventions in Ethiopia to evaluate their effectiveness in addressing water-related climate hazards and to identify key implementation gaps. The analysis revealed that deployed NbS, comprising green, blue, and hybrid interventions such as reforestation, wetland restoration, and climate-smart agriculture, have demonstrated measurable effectiveness. They reduced runoff and flood peaks, enhanced soil moisture and water storage for drought resilience, and delivered necessary socio-economic co-benefits upholding the livelihood of people. However, robust impediments stand in their way of scaling up. The analysis identified dominance of small-scale, rural pilot schemes, conspicuous lack of urban applications, the extensive absence of integrated economic cost–benefit studies, and an insufficient mechanism for cross-regional learning. We conclude that a concerted effort is needed to transition NbS from small-scale pilots to the cornerstone of Ethiopia's national climate resilience strategy. On the Ethiopian national level, it is imperative for the federal institutions to emphasize the integration of Nature-Based Solutions into policy frameworks. The regional and local administrations play a significant role in the implementation and funding of effective measures at broader scales. The development partners, alongside NGOs, must concentrate on improving monitoring capacities and sharing knowledge for the replication of best practices. All these entities are important for the upscaling of Nature-Based Solutions.</p>